c. 1825, "to unravel" (of clothing), from East Anglian variant of 17c. fasel "to unravel, fray" (as the end of a rope), from Middle English facelyn "to fray" (mid-15c.), from fasylle "fringe, frayed edge," diminutive of Old English fæs "fringe, border." Related: Frazzled, frazzling. Compare German Faser "thread, fiber, filament," Middle Dutch vese "fringe, fiber, chaff." Probably influenced in form by fray (v.).